Pharmacodynamics is the drug-induced response of a biological system and it can be assessed and quantitated using molecular, physiological and medical imaging techniques. As part of DCTD?s support for targeted cancer therapies, it is necessary to develop useful and reliable assays that can guide drug development and be used to understand the biochemical changes that are part of the evaluation of drug response in clinical trial patients. This project supports the design, development, validation and demonstration of fitness-for-purpose of a new multiplex assay for the analysis and quantitation of important biological markers of tumor cell death or survival. These robust assays will be created to support testing of humor tumor biopsies collected during the conduct of human clinical trials and will investigate the linkage between ER stress, oxidative DNA damage and repair, and tumor cell death.